I just snapped, I'm afraid, and did something which may be regarded as a little OTT!
Full two page ad in our local paper concerning the Christmas market, which is run by the Council. Big banner across the top, containing, in quite large print, the opening hours - e.g '10.00 am to 8.00 pm on Thursday's' Six aberrant apostrophes in total!!
I have emailed the council person charged with overseeing all things Christmas market related and complained that it looks unprofessional, and am happy to offer my services as a proofreader. She's going to think I'm one of 'those' people, isn't she? 
(I just told ds2, who definitely thinks I'm one of 'those' people
)